Wii Whiteboard IR Pen



My first 3d CAD project is a new Wii Whiteboard IR pen. Maybe there's better ones out there already, but I'd like to make something better than what my wife bought, these economy IR pens. This one needs to be held backwards for us, with the IR LED pointing out the back "eraser" end to be picked up. Holding it as we think should be, the Wiimote doesn't see it on our 100" projector screen, using a Panasonic AX100U projector with a Stewart Grayhawk 100" 16:9 screen.

My hypothesis as to why our attempt to use this stuff at home failed is that the LED is focused out the writing end of the pen. That is, away from the WiiMote receiver, and I postulate that while there is an angle cone that the LED emits, that far to the side is still not as easy for the WiiMote to see it. So my idea is to put multiple LEDs around the side of the pen, rather than one pointing out the tip.

I'd like a fat pen much like the usual Expo whiteboard markers.

This discussion says that the best IR wavelength LED to use is 940nm.

I'd like to also include a standard laser pointer feature, pointing out the tip instead of the IR LED. I don't expect I'll design a laser pointer, I hope to buy a cheap laser pointer and scavenge parts out of it, basically take their existing board, wire it to my battery, and fit that with their lens into my new pen shell.